"We are happy to announce that the first set of images from Rosetta's NAVCAM has now been made available to all scientific and public users via ESA’s Planetary Science Archive (PSA). This first batch of image data covers the period leading up to 2 July 2014, prior to Rosetta’s arrival at 67P/C-G. Further releases of image data will be made in blocks on a monthly basis henceforth, with the near-term aim to catch-up so that NAVCAM data will be publicly released six months after they are taken."

If it's richer in CO2 or CO the neck region may lose mass, too.Maybe they find out more detail about the compositional variations during the close flyby to come.

Is the neck region having a different composition really a sign of CG being a contact binary? Seems to me more like a single object with more ices near the center that are now exposed? This question was touched upon at a talk last evening by Joel Parker of the Southwest Research Institute (and the ALICE instrument).

A contact binary would probably be more interesting, but I share your preference for exposure of fresh interiour material of a single object.Once the outermost crust is lost, sublimation may progress faster in that area, resulting in forming the neck.The sublimation process of a prestine rotating cometary nucleus may start either near the equator for a spin axis parallel to the orbital axis, or near one of the poles if the pole happens to be directed towards the Sun near perihelion (skipping other options).Taking the equator version the rotation axis may change (or precess) due to a change of the axis of maximum moment of inertia due to preferred mass loss of the nucleus near the equator.

This preferential sublimation process seems interesting to me in for example how it might be modeled. Good food for thought with Gerald's scenarios. It also seems plausible in explaining some other similarly shaped comets.

What still keeps me from accepting the excavated neck story are the large pits on the main body that are closest to the crack in the neck. These have the appearance of some of the other vent pits on both bodies. If they are indeed expired vents, then they had to have formed earlier than the scree/talus that now spills into them from the head. They do not match the valley wall morphology further up the neck; they are positioned facing outward relative to the main body, and circular as if not influenced by earlier neck material. I just can't conceive a history of their formation relative to neck material deflation that would have been happening at the same time, were this a unified object rather than a piece rotated into place at a later era. I see the refill history of those pits as telling something about the sequence of activity/erosion in the neck.

I'm not sure I understand that reasoning. If we assume that the perihelion passages reforms the surface of the bodies, then the main surface features of both lobes would have been shaped by the same process at the same time regardless of whether it's a contact binary or not. If it is a binary object then they presumably joined before becoming a comet after all. It might indicate that both lobes have similar/same composition, but not that 67p is necessarily a single object.

Ulamec, Taylor and the PIs of ROMAP and RPC-MAG. Live on Tuesday, 1200 to 1300 UTC+2 (CEST).Before that the stream will show previous press conferences (and something that looks like standup comedy in the press conference room in Austrian inbetween )

The above stream link offers a chat function to submit questions for the press conference remotely.

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